(a) Field of the Present Invention
The present invention discloses to use a pulsed power as the power source, whereof the capacitive impedance component (or the inductive impedance component or the resistive impedance component) constitutes the first impedance, and the capacitive impedance and inductive impedance are in parallel connection whereof their parallel resonance frequency is different from the pulse period of the pulsed power, thereby to constitute the second impedance without parallel resonance, whereof the first impedance and the second impedance are in series connection, whereby the two ends of the two after series connection are arranged for inputting a pulsed power, and the voltage of pulsed power from the power source is divided by the series connected first and second impedance; According to the circuit aforementioned, the bi-directional divided alternated power in decaying wave shape is formed across the two ends of the second impedance, whereof it is characterized in that a bi-directional conducting light emitting diode is driven by the divided power, or at least two bi-directional conducting light emitting diode sets which are respectively parallel connected across the two ends of the first impedance and the second impedance are respectively driven by the divided powers across the two ends of the first impedance and the two ends of the second impedance.
(b) Description of the Prior Art
The conventional light emitting diode drive circuit using AC or DC power source is usually series connected with current limit resistors as the impedance to limit the current to the light emitting diode, whereof the voltage drop of the series connected resistive impedance always result in waste of power and accumulation of heat which are the imperfections.